Dysbiosis of the Gut Microbiota Being a Contributing Factor to Parkinson’s Disease: A Literature Review

Parkinson’s disease (PD) is a prevalent neurodegenerative disorder characterized by symptoms such as tremors, dementia, and bradykinesia. Early non-motor signs, including constipation and hyposmia, suggest a potential connection between PD and the gut. The loss of dopaminergic neurons in the substantia nigra is a hallmark of PD, with unknown causes. While current treatments provide symptom relief, there are no therapies to slow the progression of the disease. The gut microbiota plays a role in inflammatory and immune responses and has been implicated in neurological disorders. The connection between gut microbiota and neurodegenerative disease remains unclear. In this review, we explored the potential link between gut microbiome dysbiosis in PD, focusing on constipation, an early disease symptom. Our review examined the evidence suggesting that chronic intestinal inflammation may contribute to the development of PD and implicate further connections to other neurodegenerative diseases.